Dissipation, transfer and safety evaluation of emamectin benzoate in tea

Food Chem. 2016 Jul 1:202:199-204. doi: 10.1016/j.foodchem.2015.11.069. Epub 2015 Nov 14.

Abstract

The dissipation and residue of emamectin benzoate in tea leaves and the residue transfer from tea leaves to tea brew were investigated by modified QuEChERS (quick, easy, cheap, effective, rugged and safe) combined with ultra performance liquid chromatography tandem mass (UPLC-MS/MS). The average recoveries ranged 85.3-101.3% with relative standard deviation (RSD) less than 15%. The limits of quantification (LOQ) were 0.005mgkg(-1) in tea leaves and 0.0004mgL(-1) in brew. Emamectin benzoate dissipated rapidly in tea with half-life (t1/2) of 1.0-1.3days. The terminal residues of emamectin benzoate were less than 0.062mgkg(-1). The leaching rate of emamectin benzoate from freshly-made tea to brew was <5%. The risk of emamectin benzoate at the recommended dosage was negligible to humans depending on risk quotient (RQ) value, that was lower than 1 significantly. This study could provide guidance for the safe use of emamectin benzoate and serve as a reference for the establishment of maximum residue limits (MRLs) in China.

Keywords: Dissipation; Emamectin benzoate; Tea; Transfer; Ultra performance liquid chromatography–tandem mass spectrometry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Camellia sinensis / chemistry*
  • China
  • Chromatography, Liquid
  • Food Contamination*
  • Half-Life
  • Ivermectin / analogs & derivatives*
  • Ivermectin / analysis
  • Plant Leaves / chemistry*
  • Tandem Mass Spectrometry
  • Tea / chemistry*
  • Tea / standards

Substances

  • Tea
  • Ivermectin
  • emamectin benzoate